Motion sensors or occupancy sensors are devices that detect movement or presence within a defined area.
They are commonly used in homes and offices to turn lights on and off automatically.
There are two types of motion sensors: passive infrared (PIR) and ultrasonic.
PIR sensors detect movement using heat signatures.
Ultrasonic sensors emit sound waves at specific frequencies and measure the time it takes for them to bounce back.
These sensors can be wired directly into an electrical circuit, which turns the light on when someone enters the room, or they can be mounted on walls or ceilings.
Types Of Motion Sensors
Passive Infrared (PIR) sensors detect movement by sensing changes in temperature caused by people moving through its field of view.
It is most sensitive to warm bodies, but will also sense cold objects such as food containers or refrigerators.
The sensor sends out pulses of infrared energy from one or more emitter elements.
When these pulses hit a person or other object, some of the energy bounces back toward the sensor.
This reflected energy is detected by a detector element.
The intensity of the returned signal indicates how much energy was absorbed by the object.
A high-gain amplifier amplifies the weak signal before it reaches the microcontroller.
Ultrasonic sensors emit sound waves at specific frequencies.
As the sound wave hits an obstacle, part of the wave reflects back towards the source.
By measuring the elapsed time between sending the sound wave and receiving the echo, the distance to the obstacle can be determined.
An ultrasonic sensor has no moving parts and therefore requires less maintenance than other types of sensors.
Wiring A Motion Sensor
Motion sensors usually require a power supply. If you’re wiring your own sensor, use a low-voltage transformer with a voltage rating of 24 volts DC.
You may need to replace the original bulb with a dimmer switch rated for 12 volts AC. Use a standard screwdriver to remove the cover plate.
Remove the screws holding the base plate in place. Locate the wires leading to the bulb socket. Cut the wire closest to the bulb socket.
Strip about 1 inch of insulation from each end of the wire. Twist the bare ends together and solder them securely.
Repeat this process for all three wires. Connect the black wire to the positive terminal (+), red wire to the negative (-) and green wire to ground (0).
Reinstall the baseplate and secure it with the included screws. Replace the cover plate and reattach the mounting bracket.
Plug the motion sensor into a wall outlet and test it to make sure it works properly.
Motion Sensor Installation Tips
For best results, install motion sensors near doorways and windows where there is likely to be activity.
Make sure motion detectors are installed away from water sources.
Avoid placing motion sensors in areas that receive direct sunlight because the sensor’s internal battery will drain quickly.
Don’t put motion sensors in places where pets might knock them over.
Consider installing motion sensors in rooms where children frequently play.
Install motion sensors in bathrooms, so you’ll know if someone gets up during the night.
Install a motion sensor in your garage to monitor who comes and goes.
Place motion sensors on both sides of doors and windows to help reduce false alarms.
Motion sensors should not be placed directly under heat lamps. They could trigger an alarm when the lamp isn’t even turned on!
Don’t place motion sensors inside closets or cabinets. These locations can cause false alarms.
Best Places For Motion Sensors
There are many places around the house where you can mount a motion sensor. Here are some ideas:
- Under-cabinet lights – Under cabinet lighting is often used in kitchens and laundry rooms. Install a motion sensor here to keep track of who enters those spaces.
- Garage – Motion sensors mounted in garages can alert homeowners to unauthorized vehicle access or break-ins.
- Patio – Motion sensors mounted outside can detect intruders sneaking onto your patio.
- Laundry room – Motion sensors mounted in laundry rooms can prevent theft.
- Basement – Motion sensors mounted in basements can detect intruders entering the home.
- Bathroom – Motion sensors mounted in bathroom mirrors can alert homeowners to people using the restroom at night.
- Kitchen – Motion sensors mounted above kitchen sinks can detect intruders breaking into the home.
- Bedroom – Motion sensors mounted above bedroom dressers can detect intruders trying to steal items from the closet.
- Bedside table – Motion sensors mounted above bedside tables can detect intruders looking for valuables stored there.
- Study – Motion sensors mounted above study desks can detect intruders looking through files or documents.
- Kids room – Motion sensors mounted above kids’ beds can detect intruders snooping around the room. It can also ensure your child’s safety and actions.
How Much Do Motion Sensors Cost?
The cost of motion sensors depends on whether they’re hardwired or wireless.
Hardwired models typically run $10-$20 per unit, while wireless versions start at $15 per unit.
Wireless units have no physical connection between the sensor and the controller. Instead, they communicate with each other wirelessly via radio frequency (RF).
Some wireless motion sensors come equipped with batteries that last about one year.
Others use rechargeable batteries that last anywhere from two weeks to six months.
Wireless motion sensors are more expensive than their wired counterparts but offer several advantages.
They don’t require any wiring and can easily be installed without professional assistance.
If you install a wireless model yourself, it won’t take long before you’re saving money by doing so.
You’ll still need to purchase a controller, which runs about $30. But if you already own a compatible wireless router, you can skip this step.
If you want to save money, consider buying a kit that includes both the sensor and the controller together.
Kits usually include everything you need to get started. You’ll pay less for the kit because you don’t have to buy the parts separately.
However, you may not get as much flexibility when installing the system.
For example, you might not be able to place the sensor wherever you like.
How To Setup A Motion Sensor System
Motion sensors work best when placed near an area where someone is likely to enter.
The most common locations are garage doors, entryways, windows, sliding glass doors, and back door entrances.
You should select a spot that will allow you to see anyone who enters the space.
Also make sure the location doesn’t interfere with normal activities such as walking, running, or playing sports.
When selecting a motion sensor, look for one that has been tested and proven effective.
Most manufacturers test their products thoroughly before releasing them to consumers.
Manufacturers also provide instructions on how to set up the device.
Follow these instructions carefully. Otherwise, you could damage the sensor or cause false alarms.
To avoid false alarms, keep in mind that some people tend to move furniture or walk around even when nobody else is home.
This can trigger a false alarm. So if you notice movement in areas where there shouldn’t be any activity, check the house first.
Then contact the manufacturer directly to find out what caused the problem.
Once you’ve selected a motion sensor, connect it to the controller using the included wires.
Make sure the sensor is plugged into the wall outlet and the power cord is securely connected to the battery.
Next, plug the controller into your computer’s USB port and turn it on. When prompted, choose “Install” from the program’s menu.
The installer software will guide you through the setup process. It will ask you to specify the name of the sensor and its location.
Once you finish setting up the sensor, click “Finish.”
The installer will then prompt you to create a user account. Enter the username and password you created during installation.
Click “Next,” and follow the prompts to complete the setup process.
You now have a working motion-sensing system!
Best Motion Sensors
There are countless motion sensors available on the market today. Some are inexpensive, while others cost thousands of dollars.
Below we list some of the best options based on price, features, and reliability.
PIR Sensor Dual Passive Infrared Motion Detector
This wired motion detector detects movement by sensing infrared radiation emitted by warm bodies.
It works well for detecting intruders but won’t detect pets or animals. PIR sensors are easy to install and use.
They’re often used in residential applications, including garages, entryways, and basements.
- Works great for detecting human presence
- Easy to install
- Can be mounted indoors or outdoors
- Uses passive infrared technology to sense moving objects
12V Wired PIR Motion Detector Alarm Infrared Sensor
This 12 volt wired motion detector uses passive infrared technology to detect movement. It can be installed anywhere in the home or business.
It’s ideal for detecting intruders and can be used to ensure the protection of your home.
The sensor is also easy to install and can be easily wired into your house’s mainframe.
- Detects movement with passive infrared technology
- Mounting bracket included
- Wireless option available
- 360-degree monitoring system
Maxxima High Bay Fixture Mount 360 Degree PIR Occupancy Sensor
This high bay fixture mountable PIR sensor is designed to work with Maxxima’s Maxxima Home Security System.
It provides 360 degrees of coverage and alerts users when someone enters or leaves a room.
The sensor can be mounted inside or outside a building. It has an IP66 rating which means it’s dustproof and water-resistant.
- IP66 rated
- Mounting hardware included
- Waterproof design
Heath Zenith S SL-5407-BZ 180-Degree Replacement Sensor
This replacement sensor is designed to replace Heath Zenith’s SL-5407-A180-BZ.
This sensor offers 180 degree coverage and is compatible with their wireless security systems.
It comes with mounting brackets that allow you to place the sensor in any area where you need to monitor activity.
The sensor also features a detection rate of up to 70 feet.
- Compatible with Heath Zenith’s wireless security systems
- 180-degree coverage
- Detection range of up to 70 ft
- Mounting brackets included
- 120 VAC power requirement
Bosch ISC-BPR2-W12 Blue Line Gen2 PIR Motion Detector
The Bosch ISC-BPR2-W12 blue line gen 2 PIR motion detector is a popular choice among homeowners because it’s affordable and reliable.
It works well to protect homes from burglars and other unwanted visitors.
The sensor includes a mounting kit so you can install it in almost any location. The sensor is UL listed and meets all safety standards.
- UL listed
- Mounting kit included
- Power supply included
- 10-foot cable length
- 1-Year Warranty
J.LUMI YCA1050 PIR Motion Sensor Light Switch 2000W
The J.LUMI Yca1050 PIR control switch is a dimmable light switch that can be used as a PIR sensor.
It has a 10-foot cord and is suitable for both indoor and outdoor installations. The sensor will turn on lights when people enter a room.
It has a maximum output of 2000 watts and a minimum input of 4 volts DC.
- On” and “Off” buttons
- Dimming control
- 2000 watt max output
- 4VDC min input
- 3 Years Limited Warranty
If you’re looking for a simple way to keep track of who’s coming and going, then a PIR motion detector could be just what you need.
They are very inexpensive and offer great value for money. You can even wire the sensor yourself using the steps outlined above.
We hope that you found this article helpful and that it provided some useful information.